Field of the Invention
The present invention relates to a method and a circuit arrangement for transmitting cells, that are referred to below as message packets, and is more particularly concerned with reducing the loss of transmitted message packets which are transmitted in accordance with an asynchronous transfer mode for message packets on offering lines during the course of virtual connections.
More specifically, the present invention relates to a method into a circuit arrangement for forwarding message packets that are transmitted according to an asynchronous transfer mode on offering lines during the course of virtual connections and comprise a packet header which identifies the respective virtual connection to the serving lines via a packet switching equipment that comprises at least two redundant switching matrices, the serving lines being connected to the packet switching equipment, whereby a message packet group having a plurality of identical message packets comprising to the number of redundant switching matrices is formed by a multiplication for each of the message packets transmitted on one of the offering lines during the course of a virtual connection. An identical auxiliary identifier that changes for successive message packet groups is attached to each of the message packets on the message packet group and the message packets of the message packet group are separately transmitted via the redundant switching matrices towards the serving line coming into consideration for the respective virtual connection. After such a transmission via the redundant switching matrices on the basis of the auxiliary identifier respectively attached to the message packets, only one of the message packets belonging to a message packet group is forwarded to an allocated serving line.
Such a method and such a circuit arrangement have been disclosed, in general, in the European patent application 89103798.8.
In this method or in this circuit arrangement, a loss of an entire message packet cycle that can cover, for example, a plurality of 64 message packets can occur given a faulty transmission of a message packet.